tolaria/docs/adr/0013-remove-theming-system.md

type, id, title, status, date, superseded_by

type	id	title	status	date	superseded_by
ADR	0013	Remove vault-based theming system	superseded	2026-03-23	0081

Context

Laputa had a vault-based theming system where themes were markdown notes in theme/ with type: Theme frontmatter. Each property became a CSS variable. This included a ThemeManager hook, theme property editor, dark mode detection, live preview on save, and three built-in themes. The system was complex (spanning Rust seed/create/defaults modules, TypeScript hooks, and CSS variable bridging) and added significant maintenance burden for a feature that most users never customized beyond the defaults.

Decision

Remove the vault-based theming system entirely. The app uses a single, hardcoded light theme defined in CSS variables (src/index.css) and editor theme (src/theme.json). The theme/ folder, ThemeManager hook, theme Rust modules, theme property editor, and dark mode support were all deleted.

Options considered

• Option A (chosen): Remove theming, ship a single polished light theme — drastically reduced complexity, fewer files to maintain, no theme-related bugs. Downside: no user customization, no dark mode.
• Option B: Keep theming but simplify — reduce to light/dark toggle only. Downside: still requires theme loading, CSS variable bridging, and live preview infrastructure.
• Option C: Keep the full theming system — maximum flexibility. Downside: high maintenance cost for a rarely-used feature, frequent source of bugs (WKWebView reflow issues, CSS var sync).

Consequences

• Deleted: src-tauri/src/theme/, src/hooks/useThemeManager.ts, ThemePropertyEditor.tsx, theme-related commands, _themes/ legacy support.
• Single theme defined in src/index.css (CSS variables) and src/theme.json (editor typography).
• No dark mode support — the app is light-only.
• Protected folders reduced: theme/ is no longer scanned by scan_vault.
• Re-evaluation trigger: if dark mode becomes a hard requirement for accessibility or user demand.